Abstract:
As the first animals on earth to evolve aerial locomotion, insects took off into the sky 350 million years ago and have been experimenting successfully with aerodynamics, sensory systems and flight control though evolution. They have developed sophisticated design of flight sensing, control and actuation system that allow them to master the complex physics in their living environments and achieve supreme stability and maneuverability. These relatively simple, but also sophisticatedly designed flying machines offer us a treasure trove of scientific problems and inspirations for engineering designs. Decoding the secret of insect flight demands multi-disciplinary approaches that interconnect engineering, mathematics and biology. Our research starts from assessing the flight performance of insects and hummingbirds using a variety of experiments and then through using biomimetic robotic devices, dynamic modeling, control theories and fluid experiments, we work towards understanding the flight dynamics, sensorimotor control and aerodynamics of insect flight. Eventually, the knowledge of insect flight will serve as the basis to develop millimeter-scale micro air vehicles (MAVs) in the future.

Bio:
Dr. Cheng is an Assistant Professor of Mechanical Engineering at Penn State. Prior to this, he was a Postdoctoral Research Associate in the School of Mechanical Engineering at Purdue University, where he received his Ph.D. in 2012. He also received his M.S. in Mechanical Engineering from University of Delaware and B.S. from Control Science & Engineering at Zhejiang University, China. His research interests include biomechanics and sensorimotor control of animal flight, aerodynamics at low Reynolds number and biologically inspired robotics. Working in a highly interdisciplinary field, Dr. Cheng's work has been published in journals from many disciplines, such as Science, IEEE Trans on Robotics, Journal of Experimental Biology, Experiments in Fluids and Journal of the Royal Society Interface. Dr. Cheng received National Science Foundation (NSF) Early Career Development (CAREER) Award in 2016.

Nitin Sharma
Department of Materials Science and Engineering, University of Pittsburgh

Wednesday, November 16, 2016 3:35pm - 4:25pm
103 Leonhard Building

Abstract:
Functional Electrical Stimulation (FES) can be used to artificially activate paralyzed lower limb muscles to restore walking and standing function in persons with neurological disorders. Despite its potential, FES-based walking neuroprosthesis has achieved limited acceptability among persons with paraplegia. This is primarily due to the early onset of muscle fatigue during FES and difficulty in obtaining a consistent and reliable response from the paralyzed muscle using traditional control methods.

We are employing a hybrid strategy that integrates FES with a powered exoskeleton to overcome these hurdles. This hybrid strategy has several advantages. The main advantage is that the effects of muscle fatigue and any inconsistent response from FES can be compensated by the active exoskeleton. This can potentially lead to improved functional mobility in users with neurological impairments. Other advantages include reduced overall weight of the exoskeleton and neuroplastic improvements in the neuromuscular system due to FES.

However, closed-loop control methods are required to effectively integrate FES with a powered exoskeleton because the hybrid combination leads to redundancy in actuation and needs a criteria to allocate control between FES and an electric motor. I will be presenting algorithms and models that were recently developed by our research group to control the hybrid exoskeleton. These methods include 1) a muscle fatigue model to inform the onset of muscle fatigue and muscle recovery during FES, 2) Shared control of FES and electric motor based on the fatigue model, and 3) muscle synergy inspired control of a hybrid walking exoskeleton.

Bio:
Nitin Sharma received his Ph.D. degree from the Department of Mechanical and Aerospace Engineering, University of Florida, Gainesville, in 2010. He was an Alberta Innovates-Health Solutions postdoctoral Fellow in the Department of Physiology at the University of Alberta, Edmonton, Canada. Since 2012, he is an Assistant Professor in the Department of Mechanical Engineering and Materials Science at the University of Pittsburgh. His research interests are modeling, optimization, and control of functional electrical stimulation-elicited walking. His current research in hybrid exoskeletons is funded by two NSF awards and one NIH R03 Award.

Wei-Heng Shih
Department of Materials Science and Engineering, Drexel University

Wednesday, November 9, 2016 3:35pm - 4:25pm
103 Leonhard Building

Abstract:
We have developed a method of coating Mg(OH)2 layer on Nb2O5 particles that facilitated the direct, one-step, sintering of piezoelectric lead magnesium niobate-lead titanate (PMN-PT) freestanding sheets. The piezoelectric freestanding sheets were used to develop a novel Piezoelectric Plate sensor (PEPS). By immobilizing receptors specific to target antigens on the PEPS surface, binding of target antigens such as cells, viruses, proteins, and DNA in various liquid environments to the receptor on the sensor surface causes the PEPS resonance frequency to shift. For example, PEPS can rapidly (< 30 min) detect double-stranded DNA at a concentration of 60 copies/ml point mutation in the background of 1000 times wild type in urine or serum and genetic signature of bacteria at 150 copies/ml in stool without isolation, concentration, and amplification. PEPS’s enhanced detection sensitivity is related to the easy domain switching in PMN-PT layer caused by the target antigen binding to the sensor surface. .
Meanwhile, we have also developed an environmentally friendly aqueous method to synthesize aqueous quantum dots (AQDs) using mercaptopropionic acid (MPA). Due to high coverage of the capping molecules, AQDs exhibited a better than 80% conjugation efficiency and were colloidally stable. Visible and Near-infrared (NIR) AQDs were used to create a molecular probe to image cancer cells on tumors to help surgeons determine whether all cancer cells have been removed in the operating room. More recently, we studied the synthesis of organohalide perovskite materials to develop highly photoluminescent nanocrystals as well.

Bio:
Wei-Heng Shih received a B.Sc. in physics in 1976 from Tsing-Hua University in Taiwan and completed his Ph.D. degree in Physics in 1984 from Ohio State University. He joined the Department of Materials Science and Engineering at Drexel University in 1991 and was promoted to Professor in 2003. His research has covered colloidal processing of ceramics; sol-gel processing of microporous and mesoporous ceramic powders; and chemical treatment of combustion wastes. His current research interests are fabrication, characterization and design of piezoelectric plate sensors and the development of environmentally friendly synthesis of photoluminescent nanocrystals (quantum dots) for biomedical and optoelectronic applications. Prof. Shih has 132 published journal papers, 32 patents and 24 patents in application. He received the 1999 Edward C. Henry Electronics Division Best Paper Award from The American Ceramic Society and was elected a Fellow of National Academy of Inventors in 2013. In Drexel University, he has received several awards including the Faculty Achievement Award, Professor of the Year, and the Research Achievement Award. His technologies have been licensed by four companies.

Abstract:
Terminating lines of surfaces of discontinuity serve as a model of common line defects that arise in a host of materials; dislocations and grain/phase boundary junctions in crystalline and soft matter. I will describe a framework for considering line defect dynamics within continuum mechanics. The theory will be illustrated with examples related to dislocation dynamics with inertia, dislocation nucleation, and the computation of fields of interfacial defects like the star disclination and grain boundary disconnections.

Bio:
Amit Acharya is a Professor in the Mechanics, Materials, and Computing group of the Department of Civil & Environmental Engineering at Carnegie Mellon University (CMU). He also holds a courtesy appointment in the Dept. of Materials Science and Engineering at CMU and a Visiting Professorship in the Dept. of Mathematical Sciences at the University of Bath, UK. He received a PhD degree in Theoretical & Applied Mechanics from the University of Illinois at Urbana-Champaign (UIUC) in 1994. Subsequently, he did post-doctoral work for a year at the University of Pennsylvania and then worked for HKS, Inc. in Providence, RI (now Simulia, Dassualt Systemes) from 1995-1998, spending most of his time as a senior research engineer in the ABAQUS Std Development group. There, he was the lead developer of the *Hysteresis nonlinear viscoelastic material model and the S4, fully-integrated finite strain shell element, that are still in use in the ABAQUS general-purpose FE code. From 1998-2000, he was a Research scientist at the DOE-ASCI funded Center for Simulation of Advanced Rockets at UIUC, before joining CMU in 2000.
His honors include a Leverhulme Visiting Professorship from the Leverhulme Foundation, UK, a Rosi and Max Varon Visiting Professorship from the Weizmann Institute, Israel, and an INdAM Visiting Professorship to the University of Pavia, Italy. He has been an invited short-course lecturer at SISSA (Trieste, Italy) and has held visiting research positions at Oxford, Cambridge, Marseille, Edinburgh, and Metz.
His broad research interests are in Continuum Mechanics, Mathematical Materials Science, and Applied Mathematics. Current emphasis is on theoretical and computational defect mechanics in crystalline, liquid crystalline, and metallic glass systems, coarse-graining of nonlinear time-dependent systems and the interplay of differential geometry and structural mechanics in the design and actuation of thin sheets.

Robert J. Beaury
School of Engineering Design,Technology and Professional Programs, PSU

Wednesday, October 19, 2016 3:35pm - 4:25pm
103 Leonhard Building

Abstract:
The direct definition of entrepreneurship speaks to starting a new business. Developing an entrepreneurial mindset is critical to the success of that effort but it is also critical to a wide range of endeavors, both professional and personal.
This seminar will explore what is an entrepreneurial mindset and how it translates to creative thinking, solving real-world problems, innovation and living a more complete and interesting life.
The objective of the seminar will be to demonstrate how adopting entrepreneurial skills will benefit any individual regardless of their career aspirations. We will begin by exploring the history of entrepreneurship and the personality type and skill set of a classic entrepreneur. We will then challenge the participants to work on a series of exercises related to the development of an entrepreneurial mind-set.

Bio:
Bob has been an Instructor in the College of Engineering since 2001, teaching classes in the Engineering Entrepreneurship & Leadership Minors, including classes in the new Masters in Leadership program. In January of 2015, Bob became the Interim Director of the Engineering Entrepreneurship Minor.
Bob’s approach to teaching is based upon experiential, problem based-learning. Students work in teams to solve real-world problems that have no easy answer in a competitive environment. Creativity and innovation are key components to Bob’s classes, and several successful businesses have started as a byproduct of Bob’s classes, including OrderUp and Diamondback Truck Covers. In the spring of 2016 Bob won one of the prestigious George W. Atherton Excellence in Teaching Awards.
Prior to his work at Penn State, Bob was the CEO and President of Broadband Networks (BNI) a technology start-up that designed and built distance learning networks. BNI was acquired by NumereX in 1997.
Bob is currently a member of the Board of Directors of several companies including Restek, Rockland Manufacturing and Diamondback. He is also a co-Founder of Xsalta, a web marketing company focused on helping mental health professionals create awareness of a revolutionary treatment for depression named Transcranial Magnetic Stimulation.

Abstract:
Caries, which lead to partial or total loss of teeth, influence almost 100% adults and 60-90% of school children. To restore the function and appearance of teeth, dental crowns have been adopted as a common treatment. However, the strength and fatigue life of the crowns are not satisfactory due to many reasons. Natural teeth have superior performance both in strength and durability to the artificial dental structures. In this study, inspired by the crack resistance of the functionally graded structure of natural teeth, a bio-inspired design of functionally graded dental material was proposed to replace the conventional dental adhesive material. Numerical models were used to optimize the design. Guided by the models, nanocomposite materials were used to fabricate these graded structures. Under Hertzian contact loading, they had ~20–30% higher critical loads than conventional dental multilayers at various clinically relevant loading rates. The critical loads were also well predicted by fracture mechanics models that integrated the nanoindentation measurements and creep test of the fabricated graded materials. The failure modes of the structure were also investigated to make connections to the clinical failure modes of dental crowns.

Bio:
Dr. Jing Du is an assistant professor of mechanical engineering at Penn State University. She received her B.S. and M.S. degrees in Mechanical Engineering and Materials Science and Engineering, respectively, from Tsinghua University and a Ph.D. degree in Mechanical & Aerospace Engineering from Princeton University. Before joining Penn State, she was a postdoctoral scholar in the School of Dentistry at the University of California, San Francisco (UCSF). Her research focuses on solid mechanics and materials science. Her current areas of research interests include mechanics of biological materials and biomaterials, biomedical devices and bio-inspired design.

Yury Gogotsi
Department of Materials Science and Engineering, Drexel University

Wednesday, October 5, 2016 3:35pm - 4:25pm
103 Leonhard Building

Abstract:
Two-dimensional (2D) solids – the thinnest materials available to us – offer unique properties and a potential path to device miniaturization. The most famous example is graphene, which is an atomically thin layer of carbon atoms bonded together in-plane with sp2 bonds. In 2011, an entirely new family of 2D solids – transition metal carbides (Ti2C, Ti3C2, Nb4C3, etc.) and carbonitrides – was discovered by Drexel University scientists [1]. Selective etching of the A-group element from a MAX phase results in formation of 2D Mn+1Xn solids, labeled “MXene”. 17 different carbides and carbonitrides have been reported to date [2-5]. A new sub-family of multi-element ordered MXenes was discovered recently [2]. Structure and properties of numerous MXenes have been predicted by the density functional theory, showing that MXenes can be metallic or semiconducting, depending on their surface termination. Their elastic constants along the basal plane are expected to be higher than that of the binary carbides. Oxygen or OH terminated MXenes, are hydrophilic, but electrically conductive. Hydrazine, urea and other polar organic molecules can intercalate MXenes leading to an increase of their c lattice parameter [3]. When dimethyl sulfoxide or some other polar organic molecules were intercalated into Ti3C2, followed by sonication in water, a stable colloidal solution of single- and few-layer flakes was produced. One of the many potential applications for 2D Ti3C2 is in electrical energy storage devices such as batteries, Li-ion capacitors and supercapacitors [3-5]. Cations ranging from Na+ to Mg2+ and Al3+ intercalate MXenes. Ti3C2 paper electrodes, produced by vacuum assisted filtration of an aqueous dispersion of delaminated Ti3C2, show a higher capacity than graphite anodes and also can be charged/discharged at significantly higher rates. They also demonstrate very high intercalation capacitance (>1000 F/cm3) [4].
1. M. Naguib, et al, Advanced Materials, 23 (37), 4207-4331 (2011)
2. B. Anasori, et al, ACS Nano, 9 (10) 9507–9516 (2015)
3. O. Mashtalir, et al, Nature Communication, 4, 1716 (2013)
4. M M. Ghidiu, Nature, 516, 78–81 (2014)
5. M. Naguib, Y. Gogotsi, Accounts of Chemical Research, 48 (1), 128-135 (2015)

Bio:
Yury Gogotsi is Distinguished University Professor and Trustee Chair of Materials Science and Engineering at Drexel University. He is the founding Director of the A.J. Drexel Nanomaterials Institute and Associate Editor of ACS Nano. He works on nanostructured carbons and two-dimensional carbides for energy related and biomedical applications. His work on selective extraction synthesis of carbon and carbide nanomaterials with tunable structure and porosity had a strong impact on the field of capacitive energy storage. He has co-authored 2 books, more than 400 journal papers and obtained more than 50 patents. He has received numerous national and international awards for his research. He was recognized as Highly Cited Researcher by Thomson-Reuters in 2014 and 2015, and elected a Fellow of AAAS, MRS, ECS, RSC and ACerS and a member of the World Academy of Ceramics.

Kathleen J. Stebe
Department of Chemical and Biomolecular Enginering, University of Pennsylvania

Wednesday, September 28, 2016 3:35pm - 4:25pm
103 Leonhard Building

Abstract:
There are important physical fields, intrinsic to soft matter, which we can exploit to direct colloidal assembly. The central idea is this: When a colloid is placed in a soft host, the colloid deforms the host, with some energetic consequence. The host can be a fluid interface, a nematic liquid crystal, or a lipid bilayer membrane. In each of these examples, molding the soft matter host defines energy fields that drive colloidal assembly. In the small deformation limit, important analogies to charge multipoles guide our thinking. The value and limitations of these analogies are explored as strategies are developed for directed assembly.

Bio:
Dr. Kathleen Stebe is Deputy Dean for Research in the School of Engineering and Applied Sciences, University of Pennsylvania, as well as the Richer and Elizabeth Goodwin Professor of Engineering and Applied Science in the Department of Chemical and Biomolecular Engineering, University of Pennsylvania.

Abstract:
Data management represents one of the most important ethical aspects in engineering research. With massive data generated from theoretical, numerical and experimental research, it is crucial to understand the ethical issues behind data management. In this talk, I will first present several ethical issues in engineering research involving data generation, management and use. With a brief introduction on ethical framework for use in discussion, I will then discuss the ethical issues and considerations through one case study, and provide resources to improve ethical awareness.

Bio:
Dr. Huanyu Cheng was appointed an Assistant Professor of ESM and the Dorothy Quiggle Career Development Professor at Penn State in 2015. He earned a Ph.D. and a Master’s degree from Northwestern University in 2015 and 2011 respectively, and a Bachelor’s degree from Tsinghua University (China) in 2010. Throughout Dr. Cheng’s research career, he has worked on structural design and manufacturing of biologically inspired electronics with applications in robotics, biomedicine, and energy. Dr. Cheng has co-authored over 50 peer-reviewed publications, and his work has been recognized through the reception of numerous awards.